Improvement in head-blocks



N, PETERS. PHOTO-UTHUGRAPHER. WASMNGTON. D. C.

UNTTED STATES PATENT union.

J OI/IN F. COOK, OF BALTIMORE, MARYLAND, ASSIGNOR TO GEORGE F. PAGE, JOSEPH ROBERTS, AND GEORGE L. MOOAEIAN, OF SAME PLAGE.

Specification forming part of Letters Patent No. SL93?, dated December 15, ISGS.

To all whom it may concern:

Be it known that I, J OHN- F. COOK, of the city and county of Baltimore, and State of Maryland, have invented a new and Improved Mode of Operating Head-Blocks for Circular- Saw Mills; and I do hereby declare the following to be a full, clear, and exact description of the same, sufficient to enable others skilled in the art to which the invention appertains to fully understand and use it, reference being had to the accompanying drawings, forming part of this specification, and in which- Figure I is a side elevation. Fig. 2 is a plan view, and Fig. 3 a side elevation of the elbow and wheel that moves it.

This invention consists in placing the shaft (with which a set of head-blocks for circular-saw mills is oftentimes combined in such manner that the blocks may slide longitudinally upon the shaft) upon the back side of the carriage which supports both head-blocks and shaft,

in order that, when the elbows which slide upon the blocks are made to project so far beyond the side of the carriage as to produce an equilibrium, either bloelr may be tipped upon the shaft as a fulcrum, and the whole weight of the block and elbow thus be concentrated upon the shaft, whereby one block may, with comparative ease, be slid along upon the shaft in order to effect an adjustment of its distance with respect to the other block, the shaft also imparting motion, by means of connectinggear, to the said sliding elbows, and thus discharging the double function of a fulcrum for the head-bloclrsand a propeller for the elbows.

The invention also consists in adjusting, upon the aforesaid shaft, the mechanism for producing a simultaneous movement of the sliding elbows, and also other mechanisms for giving each elbow an independent motion.

The invention also consists in adjusting the lever which operates the shaft to produce the aforesaid simultaneous movement of both elbows, by means of which said elbows may be moved a greater or smaller distance, as may be desired, at each throw of the lever.

The invention also consists in so arranging the mechanism for producing the aforesaid independent motion of each elbow with refer- .ence to the mechanism for producing the simultaneous motion of both elbows that one shall operate as a checl; upon the other, and vice versa.

In the drawings, A represents a moving carria-ge, such as is ordinarily used in saw-mills. B B represent a pair of head-blocks, also of common construction, whose function it isfas is well understood, to support the log which is to be sawed, it lying transversely across them. C C represent the usual east-iron elbows, sliding in grooves in the upper surfaces of the blocks B I3, the office of said elbows being to support and adjust the log, which rests against their vertical parts, with reference to the saw.

In all thesejparts there is nothing new, either in construction or operation.

D is a shaft, passing transversely through the head-blocks B, in such manner that the latter may slide upon it, and supported in brackets d d, projecting from the rear side, or side opposite the saw of the carriage.

The head-blocks B are pivoted upon the said shaft, and when, by the agency of the shaft itself, as will hereinafter be explained, one or both of the elbows C C are brought baclr and made to project so far beyond the sha-ft as to produce an equilibrium, the block and elbow may be tipped up on the shaft, their whole weight thus be concentrated upon the shaft, and the entire apparatus, weighing usually five hundred pounds, or thereabout, be easily slid along upon the shaft by one man toward or from the other head-block, so as to adjust the distance between the blocks to suit the length of log` to be sawed. This whole effect is produced by placing the shaft upon one side of the carriage, where therelis a clear space for the tipping of the blocks.

It is no new thing to place the shaft between the beams of the carriage; but when it is in this-position it is obviouslyimpossible for the blocks to be tipped, and they can only be adjusted along the shaft by a much greater exertion of strength than is required by my present arrangement, having, it is evident, to be slid upon the carriage as well as on the shaft. I therefore deem the placing ofthe shaft upon one side of the vcarriage a proper subject for a claim.

A groove, d, runs the whole length of the shaft D.

Between the head-blocks is an arm,` a, encircling the shaft at its lower end, and made fast thereto, but so that it may nevertheless slide longitudinally by the feather a tting in the groove d. The arm a contains a socket in its upper end for the reception of a lever, a.

Outside the head-blocks two wheels,b b, are loosely placed upon the shaft, and just on the inside of each wheel is a lever, c, also loosely attached to the shaft.

Each lever c is provided with a pawl, c', opf erating in connection with a spring, c, which pawl engages with teeth 11 on the rim of the wheels I), each tooth representing` a forward movementl of the elbow of an eighth of an inch. t

On the opposite side of each wheel b is an arm, c, in all respects similar to the arm a., and connnected, like that, with the shaft D by means of a feather, c.

A pawl, c, is attached to each arm e, which pawl likewise engages with the teeth on the rim of the wheel b, said rims being made wide 'enough to each accommodate the two pawls without contact of the latter.

A toothed wheel, h, loosely attached to the shaft and rigidly connected with the wheel l), projects up through each head-block into t-he groove in the upper surface of each block, and engages with corresponding teeth on the under side of each elbow C through the arm c c and wheels 7L and b, and any movement of the shaft is communicated to the elbows.

The shaft receives motion from either of the arms e e a, as may be most convenient, bymeans of the lever a, which is transferable from one arm to another at pleasure.

The arms a e e being all rigidly attached to the shaft, and the shaft being connected with the elbows O (J, all as before described, any movement of either arm produces a simultaneous movement of both elbows, which movement is necessary whenever it is desired to set both ends of a log over an equal distance, so as to saw stuff of uniform thickness or width.

The levers c, being loosely attached to the shaft, do not partake of its motion 5 and when either of the said levers is brought into con nection with either of the wheels b by means of the pawl c', an independent motion may be imparted to either of the elbows, the wheels b being connected with said elbows, as before explained, through the toothed wheels h, which motion is necessary whenever it is desired to set one end of the log over, and not the other, as to saw a straight side on a tapering log. Thus an independent motion to either elbow, or a simultaneous motion to both, may be imparted from the same sha-ft.

To the arm c is pivotedfa small socket, e', through which passes a rod, 7c, the lower cud of which is pivoted in a standard, 7b', on the screw, may be placed at any pointon said rod to check the forward mot-ion of the arm a, and thus limit the distance the elbows travel during their simultaneous movement at each throw of the lever. boards one inch in thickness, I have only to set the stop 7c at such a point on the rod k as to arrest the forward motion of the arm a when it moved just an inch. I then move the arm a back over a sufficient number of the teethb to allow for the width of the saw-kerf, and throw it forward again till it meets the stop. Thus, if the saw-kerf be a .quarter of an inch in width, I move the arm a back past two of the teeth b', and then forward again to the stop, when it is in just the position to cut an inch board. For stuff of any other thickness it may be adj usted accordingly.

As before explained, the pawl c of the lever c and the pawl e of the arm e both move past each other over the rim of the wheel b. Each of these pawls is double, being suspended by a pivot at its center to its own arm or lever.

Let us suppose the lever o with its pawl to be engaged in imparting to the elbow its independent motion toward the saw. In this case the forward prong of the pawl c will be the one that engages with the teeth b during the forward throw of the lever c, and slips over them during its backward throw.

To prevent the pawl c from rotating the wheel b in the wrong direction during its backward throw, the forward prong of the pawl e may be made to engage with the teeth b', its arm le being stationary the while, so as to allow the wheel b to slip under it during the forward throw of the lever c, but catch in the teeth b during the backward throw of the same. The pawl c may perform the same office during the operations of the arm e and pawl e, one pawl operating as a check for the other, and vice versa.

Having thus described my invention,vwhat I claim as new, and desire to secure by Letters Patent, is-

l. The shaft D, so arranged on the rear 'side of the carriage as that, while it propels the knee, it acts as a fulerum to facilitate the lateral adjustment of the head-block.

2. The shaft D, with the arm a rigidly attached and the levers c c loosely attached, in combination with the wheels b b, also loosely attached, and the arms e e, also rigidly attached, each arm having the pawl e", and cach lever having the pawl c', all arranged to communicate an independent motion to each Thus, if it be desired to out elbow G or a simultaneeus motion to both, To the above specification of my invent-i011 substantially as described. I have signed my hand this lst day of Sep- 3. The graduated vibrating rod 7c, pivoted tember, 1868.

no the carriage at its lower end, provided with :L fixed stop, and also an adjustable stop, 7c", JOHN F. COOK. arranged as described and shown7 Willen constructed to operante in connection with the arm Witnesses:

a, substantially in the manner :md for the Y N. K. ELLSWoR'rH,

purpose speeied. EDM. F. BROWN. 

